overnight. A second deadly terror attack in southern russia, close to the site of the olympics in sochi. Dozens are dead after the two atak attacks raising security concerns. Let's bring in brian ross. Good morning. Reporter: Good morning, david. The two attacks first yesterday and then again this morning sent an unmistakable and chilling message that islamic terrorists in russian intend to do all they can to disrupt the winter games, only 400 miles and six weeks away. This was the scene this morning in russia. A new round of carnage. After an explosion on a packed trolley bus during the morning commute in the city once knowned a stalingrad, now volgograd. Translator: A heard glass shattering in the first two stories of the building. I saw -- a -- I looked out of the window. It was still dark. And I saw a bus that was -- ripped by a blast and people were running away from it screaming. Reporter: For a second day, russian investigators said a suicide bomber was responsible in what they called a clear act of terrorism that spread fear across the country. Translator: Some of them were wounded. It was a horrendous sight. I was very scared. Reporter: This morning's attack was less than 24 hours after the train station was hit by a suicide bomber in the same city. The bomb went off just after noon, on a peak travel day before the russian christmas holiday. At least 17 people were killed and dozens more injured. With these types of operations, it's not the size of the operation that matters. It's the willingness of the people executing the operation to target civilians. Reporter: The attacks five months after the leader of a nationalist group vowed to disrupt the winter olympics. I think the russian government has something to fear, the potential loss of face, the potential embarrassment to them if the terrorist sind cat can pull off problems. Reporter: President putin has vowed to create air-tight security and the olympics. Brian, thank you. Want to get to bianna golodryga with the news this morning. Breaking developments in the case of the tupelo suspect. Good morning, everyone. The same man accused of shooting

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